Implement cache for FileWidget

Some data-gathering is quite expensive and requires a QProcess, like
getting the duration, so cache it in memory using QCache. Once the cache
is filled, the UI is much snappier.

This simplifies gatherData() a bit. It's still quite a long function,
but now it doesn't create the QStandardItems any more. I moved it to a
separate function.

1 files changed, 125 insertions, 85 deletions

diff --git a/filewidget.cpp b/filewidget.cpp
index 948a5d6..e2be4e1 100644
--- a/filewidget.cpp
+++ b/filewidget.cpp
@@ -36,6 +36,7 @@
 #include "filesorter.h"
 #include "filedisplay.h"
 #include "filecopier.h"
+#include "cachedfiledata.h"
 #include "origindialog.h"
 #include "helper.h"
 #include "globals.h"
@@ -45,6 +46,7 @@
 FileWidget::FileWidget(QWidget *parent) : QWidget(parent), mCopyToMenu(0) {
     mFileCopier = new FileCopier(this);
     mCopyProgress = new ProgressDialog;
+    mFileCache.setMaxCost(500);
     connect(mFileCopier, SIGNAL(newFile(QString,QString,qint64)), this, SLOT(setupProgress(QString,QString,qint64)));
     connect(mFileCopier, SIGNAL(bytesRead(qint64)), this, SLOT(setCopyProgress(qint64)));
     connect(mFileCopier, SIGNAL(bytesReadIntval(qint64,qint64)), this, SLOT(setCopySummary(qint64,qint64)));
@@ -241,9 +243,6 @@ void FileWidget::gatherData(){
     mModel->clear();
     QStandardItem *root = mModel->invisibleRootItem();
     mModel->setHorizontalHeaderLabels(QStringList() << QChar(0x26A7) << tr("Name") << QChar(0x26A5) << tr("MIME") << tr("Duration") << tr("Size") << tr("MD5"));
-    QBrush redBrush(Qt::red);
-    QBrush greenBrush(Qt::darkGreen);
-    QBrush blueBrush(Qt::darkBlue);
 
     QMimeDatabase db;
     qApp->setOverrideCursor(Qt::BusyCursor);
@@ -256,94 +255,70 @@ void FileWidget::gatherData(){
     while(it.hasNext()){
         QFileInfo fi = it.next();
         emit statusMessage(gatherMsg.arg(fi.fileName()).arg(QString::number(count)));
-        QMimeType mime = db.mimeTypeForFile(fi);
-        QList<QStandardItem*> fData;
-        FileAttrs attr = NotPresent;
-        Helper::Duration dur;
-        for(int i = 0; i < ColumnCount; ++i){
-            QStandardItem *item = new QStandardItem;
-            item->setEditable(false);
-            if(i == Md5Column){
-                item->setFont(QFont("courier new"));
-                item->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
-            }
-            if(i == SizeColumn){
-                item->setFont(QFont("courier new"));
-                item->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
-            }
-            fData << item;
-        }
-        fData[NameColumn]->setText(fi.fileName());
-        QString md5(tr("n/a"));
-        QString duration(tr("n/a"));
-        qint64 seconds = 0;
-        if(mime.name().startsWith("video")){
-            md5 = Helper::md5Sum(fi.absoluteFilePath());
-            fData[Md5Column]->setText(md5);
-            int haveFile = md5Count(md5);
-            if(haveFile){
-                fData[IconColumn]->setIcon(QIcon(":/huge_bra.png"));
-                fData[NameColumn]->setForeground(greenBrush);
-                attr = Present;
-            }else{
-                QString complFn = fi.completeBaseName();
-                bool hasOrig = haveOrigin(complFn);
-                if(hasOrig){
-                    fData[IconColumn]->setIcon(QIcon(":/butt_plug.png"));
-                    fData[NameColumn]->setForeground(blueBrush);
-                    attr = Origin;
+        CachedFileData *fd = mFileCache[fi.absoluteFilePath()];
+        if(!fd){
+            bool insert = true;
+            fd = new CachedFileData;
+            QMimeType mime = db.mimeTypeForFile(fi);
+            fd->attr = NotPresent;
+            Helper::Duration dur;
+            QString md5(tr("n/a"));
+            QString duration(tr("n/a"));
+            qint64 seconds = 0;
+            if(mime.name().startsWith("video")){
+                md5 = Helper::md5Sum(fi.absoluteFilePath());
+                fd->md5Sum = md5;
+                int haveFile = md5Count(md5);
+                if(haveFile){
+                    fd->attr = Present;
                 }else{
-                    fData[IconColumn]->setIcon(QIcon(":/chastity_belt.png"));
-                    fData[NameColumn]->setForeground(redBrush);
-                    attr = NotPresent;
+                    QString complFn = fi.completeBaseName();
+                    bool hasOrig = haveOrigin(complFn);
+                    if(hasOrig){
+                        fd->attr = Origin;
+                    }else{
+                        fd->attr = NotPresent;
+                    }
+                }
+                QJsonDocument jDoc = Helper::ffpmegData(fi.absoluteFilePath());
+                QJsonObject jObj = jDoc.object();
+                QJsonValue durationV = jObj["format"].toObject()["duration"];
+                seconds = durationV.toVariant().toDouble();
+                dur = Helper::Duration(seconds);
+                duration = dur.toString();
+            }else if(fi.isDir()){
+                if(fi.fileName() == ".."){
+                    fd->attr = ParentDir;
+                    insert = false;
+                }else{
+                    fd->attr = Directory;
+                    insert = false;
                 }
-            }
-            QJsonDocument jDoc = Helper::ffpmegData(fi.absoluteFilePath());
-            QJsonObject jObj = jDoc.object();
-            QJsonValue durationV = jObj["format"].toObject()["duration"];
-            seconds = durationV.toVariant().toDouble();
-            dur = Helper::Duration(seconds);
-            duration = dur.toString();
-        }else if(fi.isDir()){
-            if(fi.fileName() == ".."){
-                fData[IconColumn]->setIcon(QIcon(":/up_dick.png"));
-                attr = ParentDir;
             }else{
-                fData[IconColumn]->setIcon(QIcon(":/folder.png"));
-                attr = Directory;
+                fd->attr = NoVideo;
+                insert = false;
             }
-        }else{
-            fData[IconColumn]->setIcon(QIcon(":/gaping_ass.png"));
-            attr = NoVideo;
-        }
-        if(fi.isFile()){
-            qint64 sizemb = fi.size();
-            QLocale l;
-            QString size = QString("%1").arg(l.toString(sizemb));
-            fData[SizeColumn]->setText(size);
-            if(copyDirFiles.contains(fi.fileName())){
-                fData[CopiedColumn]->setText(QChar(0x2642));
-                fData[CopiedColumn]->setForeground(blueBrush);
-            }else{
-                fData[CopiedColumn]->setText(QChar(0x2640));
-                fData[CopiedColumn]->setForeground(redBrush);
+            if(fi.isFile()){
+                qint64 sizemb = fi.size();
+                fd->size = sizemb;
+                if(copyDirFiles.contains(fi.fileName())){
+                    fd->copied = true;
+                }else{
+                    fd->copied = false;
+                }
+                ++count;
+                totalSize += sizemb;
+            }
+            fd->duration = duration;
+            fd->md5Sum = md5;
+            fd->mimeType = mime.name();
+            fd->name = fi.fileName();
+            fd->fullPath = fi.absoluteFilePath();
+            if(insert){
+                mFileCache.insert(fi.absoluteFilePath(), fd);
             }
-            ++count;
-            totalSize += sizemb;
-        }
-        fData[DurationColumn]->setText(duration);
-        fData[DurationColumn]->setData(seconds, SecondsRole);
-        fData[Md5Column]->setText(md5);
-        fData[MimeColumn]->setText(mime.name());
-        if(mime.name() == "inode/directory"){
-            fData[MimeColumn]->setText("directory");
-        }
-        for(int i = 0; i < ColumnCount; ++i){
-            fData[i]->setData(attr, AttrsRole);
-            fData[i]->setData(fi.absoluteFilePath(), FullPathRole);
-            fData[i]->setData(md5, MD5SumRole);
         }
-        root->appendRow(fData);
+        root->appendRow(constructRow(fd));
     }
     mFileView->setSortingEnabled(true);
     readHeaderData();
@@ -445,6 +420,71 @@ void FileWidget::cutOrCopy(){
     clip->setMimeData(mMimeData);
 }
 
+QList<QStandardItem*> FileWidget::constructRow(CachedFileData *fd) const{
+    QList<QStandardItem*> fData;
+    QBrush redBrush(Qt::red);
+    QBrush greenBrush(Qt::darkGreen);
+    QBrush blueBrush(Qt::darkBlue);
+    for(int i = 0; i < ColumnCount; ++i){
+        QStandardItem *item = new QStandardItem;
+        item->setEditable(false);
+        if(i == Md5Column){
+            item->setFont(QFont("courier new"));
+            item->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
+        }
+        if(i == SizeColumn){
+            item->setFont(QFont("courier new"));
+            item->setTextAlignment(Qt::AlignRight | Qt::AlignVCenter);
+        }
+        fData << item;
+    }
+    fData[NameColumn]->setText(fd->name);
+    fData[Md5Column]->setText(fd->md5Sum);
+    int attr = fd->attr;
+    if(attr == Present){
+        fData[IconColumn]->setIcon(QIcon(":/huge_bra.png"));
+        fData[NameColumn]->setForeground(greenBrush);
+    }else if(attr == Origin){
+        fData[IconColumn]->setIcon(QIcon(":/butt_plug.png"));
+        fData[NameColumn]->setForeground(blueBrush);
+    }else if(attr == NotPresent){
+        fData[IconColumn]->setIcon(QIcon(":/chastity_belt.png"));
+        fData[NameColumn]->setForeground(redBrush);
+    }else if(attr == ParentDir){
+        fData[IconColumn]->setIcon(QIcon(":/up_dick.png"));
+    }else if(attr == Directory){
+        fData[IconColumn]->setIcon(QIcon(":/folder.png"));
+    }else if(attr == NoVideo){
+        fData[IconColumn]->setIcon(QIcon(":/gaping_ass.png"));
+    }
+    qint64 size = fd->size;
+    QLocale l;
+    QString sizeStr = QString("%1").arg(l.toString(size));
+    fData[SizeColumn]->setText(sizeStr);
+    bool copied = fd->copied;
+    if(copied){
+        fData[CopiedColumn]->setText(QChar(0x2642));
+        fData[CopiedColumn]->setForeground(blueBrush);
+    }else{
+        fData[CopiedColumn]->setText(QChar(0x2640));
+        fData[CopiedColumn]->setForeground(redBrush);
+    }
+    fData[DurationColumn]->setText(fd->duration);
+    fData[DurationColumn]->setData(fd->seconds, SecondsRole);
+    QString mimeType = fd->mimeType;
+    if(mimeType == "inode/directory"){
+        fData[MimeColumn]->setText("directory");
+    }else{
+        fData[MimeColumn]->setText(mimeType);
+    }
+    for(int i = 0; i < ColumnCount; ++i){
+        fData[i]->setData(fd->attr, AttrsRole);
+        fData[i]->setData(fd->fullPath, FullPathRole);
+        fData[i]->setData(fd->md5Sum, MD5SumRole);
+    }
+    return fData;
+}
+
 void FileWidget::paste(){
     QClipboard *clip = qApp->clipboard();
     const QMimeData *md = clip->mimeData();